Gigabyte GA-686DX User Manual page 59

GA-686DX
8 Setup low memory
9 Early Cache
Initialization
A Setup Interrupt
Vector Table
B Test CMOS RAM
Checksum
C Initialize keyboard
D Initialize Video
Interface
E Test Video
Memory
F Test DMA
Controller 0
10 Test DMA
Controller 1
11 Test DMA Page
registers
12-13 Reserved
14 Test Timer
Counter 2
15 Test 8259-1 Mask
Bits
16 Test 8259-2 Mask
Bits
17 Test Stuck 8259's
Interrupt Bits
18 Test 8259
Interrupt
Functionality
Early chip set initialization.
Memory presence test.
OEM chip set routines.
Clear low 64 K of memory.
Test first 64 K memory.
Cyrix CPU initialization.
Cache initialization.
Initialize first 120 interrupt vectors with
SPURIOUS_INT-HDLR and initialize INT 00h-1Fh
according to INT_TBL.
Test CMOS RAM Checksum, if bad, or insert key
pressed, load defaults.
Detect type of keyboard controller (optional).
Set NUM_LOCK status.
Detect CPU clock.
Read CMOS location 14h to find out type of video in
use.
Detect and Initialize Video Adapter.
Test video memory, write sign-on message to
screen.
Setup shadow RAM - Enable shadow according to
Setup.
BIOS checksum test.
Keyboard detect and initialization.
Test DMA Page Registers.
Test 8254 Timer 0 Counter 2.
Verify 8259 Channel 1 masked interrupts by
alternately turning off and on the interrupt lines.
Verify 8259 Channel 2 masked interrupts by
alternately turning off and on the interrupt lines.
Turn off interrupts then verify no interrupt mask
register is on.
Force an interrupt and verify the interrupt occurred.
B-2